A Multiscale Study of Film Thickness Dependent Femtosecond Laser Spallation and Ablation

TL;DR

This study uses multiscale simulations to explore how film thickness influences femtosecond laser spallation and ablation in silver films, providing insights for precise micromachining.

Contribution

It integrates ab initio quantum mechanics, molecular dynamics, and two-temperature models to analyze film thickness effects on laser-induced spallation and ablation.

Findings

Film thickness correlates with Kelvin temperature during laser irradiation.

Laser fluence levels affect spallation and ablation thresholds.

Recommendations for improved micromachining precision.

Abstract

A multiscale studying integrating ab initio quantum mechanics, classical molecular dynamics and two-temperature model, is carried out to study film thickness dependent femtosecond laser spallation and ablation. As an interval of 130.73 nm, five silver films with increasing thickness from 392.19 nm to 915.11 nm are simulated. Absorbed laser fluences of 0.1 J/cm^2 and 0.3 J/cm^2 are chosen to observe the laser spallation and ablation. The simulation results show that film thickness has a close correlation with the Kelvin degree of heating of the laser-irradiated silver films, which further affects femtosecond laser spallation and ablation. Suggestions for precise micromachining are proposed in this paper.